Groups whose common divisor graph on $p$-regular classes has diameter three

M. J. Felipe; M. K. Jean-Philippe; V. Sotomayor

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arXiv · 2407.09910

Groups whose common divisor graph on $p$-regular classes has diameter three

M. J. Felipe·M. K. Jean-Philippe·V. Sotomayor

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Abstract

Let $G$ be a finite $p$-separable group, for some fixed prime $p$. Let $Γ_p(G)$ be the common divisor graph built on the set of non-central conjugacy classes of $p$-regular elements of $G$: this is the graph whose vertices are the conjugacy classes of those non-central elements of $G$ such that $p$ does not divide their orders, and two distinct vertices are adjacent if and only if the greatest common divisor of their lengths is strictly greater than one. The aim of this paper is twofold: to positively answer an open question concerning the maximum possible distance in $Γ_p(G)$ between a vertex with maximal cardinality and any other vertex, and to study the $p$-structure of $G$ when $Γ_p(G)$ has diameter three.

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BibTeX RIS

M. J. Felipe, M. K. Jean-Philippe, V. Sotomayor. 2024-10-30. Groups whose common divisor graph on $p$-regular classes has diameter three. https://arxiv.org/abs/2407.09910

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